Réponses

2014-04-19T09:42:52+02:00
Calculer en détaillant les étapes, puis simplifier si possible les résultats : B,C et D

B = 19/2 + 7/10 x 5/14
B = 19/2 + 7 x 5
               10 x 14
B = 19/2 + 35/140
B = 19 x 70 /  2 x 70 + 35/140
B = 1330/140 + 35/140
B = 1365/140
B = 35 x 39 / 35 x 4
B = 39/4

C = 4 x 5/12 + 7/3
C = 4 x 5 + 7/3
     1 x 12
C = 20/12 + 7/3
C = 20/12 + 7 x 4 / 3 x 4
C = 20/12 + 28/12
C = 48/12
C = 12 x 4 / 12 x 1
C = 4/1
C = 4

D = 9/11 - 8/11 x 3/4 + 5/22
D = 9/11 - 8 x 3 + 5/22
               11 x 4
D = 9/11 - 24/44 + 5/22
D = 9 x 4 / 11 x 4 - 24/44 + 5 x 2 / 22 x 2
D = 36/44 - 24/44 + 10/44
D = 46/44 - 24/44
D = 22/44
D = 22 x 1 / 22 x 2
D = 1/2